Year: 2026
Type: preprint
Abstract: We study light quark energy loss in a quark-gluon plasma using the holographic falling-string framework on a machine-learning-calibrated Einstein-Maxwell-dilaton background for three flavor configurations: pure glue, two-flavor QCD, and full QCD with strangeness. Stopping distances are computed from null geodesics as functions of reduced temperature $T/T_c$ and baryon chemical potential $μ$. For $T/T_c>1.03$, the flavor ordering of the integrated stopping distance stabilizes to $N_f=2+1>N_f=2>N_f=0$, corresponding to the quenching hierarchy $N_f=0>N_f=2>N_f=2+1$. This agrees with the flavor ordering obtained from the shooting-string $dE/dx$ when both are expressed in the reduced-temperature framework, providing a cross-check between local and integrated observables within the same holographic background. Near $T/T_c\simeq1$, the behavior is more complex due to the interplay between the $a$ and $b$ terms in $A(z)$ and the different $T_c$ values of the three systems. Finite baryon chemical potential monotonically shortens stopping distances and enhances quenching, with enhanced sensitivity near the QCD critical endpoint, consistent with expectations from RHIC beam energy scan measurements. We discuss the geometric origin of the high-$T/T_c$ flavor ordering and possible extensions to heavy-ion transport simulations.
Source: arXiv (Cornell University)
Authors: Zhu, Huwei, Ma, Ke, Zhang, Zi-qiang
Institution: China University of Geosciences
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Award: G5334749420
OpenAlex ID: W7196998522